A primary tunnel in an Ethernet network may relay packets from a first packet switch through a network of intermediate packet switches to a second packet switch. Often, one or more backup tunnels associated with the primary tunnel are also provisioned to provide redundancy. Like the primary tunnel, the backup tunnels relay packets from the first packet switch to the second packet switch. However, the backup tunnels may traverse physically different paths than the primary tunnel through the network of intermediate packet switches to reduce the possibility that an outage affecting the primary tunnel will also affect the backup tunnels.
Although the backup tunnels may traverse a physically different path than the primary tunnel, the backup tunnels perform the same function as the primary tunnel, namely to relay packets from the first packet switch to the second packet switch. If the primary tunnel becomes non-operational, for example due to a planned or unplanned outage, the primary tunnel may be deactivated and one or more of the backup tunnels may be activated. Typically, either the primary tunnel or one of the backup tunnels is active at a time, the other tunnels being inactive. An active tunnel may relay packets while an inactive tunnel may be precluded from relaying packets even if the inactive tunnel is capable of relaying packets.